Density

Density Density is the relationship between an object’s mass and its volume. Mass is the amount of ‘stuff’ in an object. Volume is the amount of space that object occupies. Density = Mass Volume Weight is the heaviness or mass of an object. Displacement is the change in water level caused by immersion of an object.

Temp and Pressure The factors that have the greatest effect on density are Pressure and temperature. As pressure increases, so does density. It’s a direct relationship. As temp increases, density decreases. It’s an inverse relationship.

Increasing pressure generally causes an increase in density by decreasing the volume.

Increasing temperature causes a decrease in density because heating objects generally causes them to expand, increasing the volume.

Size and shape have NO EFFECT on density! The same object will always have the same density – as long as the pressure and temperature are the same.

Matter Matter comes in three states: Solid ~ Most dense Liquid ~ Moderate density Gas ~ Low density Generally speaking, the highest density is usually in the solid state, except for water. Water is most dense in its liquid state.

Liquid Density Liquids have unique densities depending on what they are. For example: Water = 1 g/cm3 Glycerine = ~ 1.25 g/cm3 (Greater than water) Vegetable oil = ~ 0.91g/cm3 (less than water) Oil Water Glycerine

So. . . Pressure and temperature are the two factors that have the greatest affect on density. Mass and volume are the variables we measure to calculate density. Size and shape have no affect on density. Objects that are the same substance always have the same density, regardless of size and shape.

Therefore . . . Density is a ratio between mass and volume. Mass is the amount of ‘stuff’ in an object and volume is how much space that object occupies. As pressure increases, so does density. (A direct relationship). Inversely, as temperature increases, density decreases because of increasing volume. (An inverse or indirect relationship).